This forum thread on adobe.com seems to offer a solution to this problem.
Key quote, by one user named "wizzi_vt":
-Dcoldfusion.disablejsafe=true
in yourjvm.config
will prevent these errors. I believe it will also remove the Bsafe encryption methods from the encrypt function documented as having been added in CF8.
Tomalak
2009-12-02 10:25:57